The embodiments described herein relate generally to a printed circuit board, and more particularly, to methods and systems used to increase distances for creepage paths for electrical components coupled to the printed circuit board.
Electrical systems and signal transmission lines can be subjected to voltage surges induced by factors such as lightning, multiple pulses and/or disturbances in power supply. In some known electrical systems, electrical components, such as optocouplers, can provide electrical isolation in response to hazardous voltages. Optocouplers can block high voltages to prevent a voltage surge in one part of the electrical system from disrupting and/or destroying other parts of the electrical system. More particularly, an optocoupler can connect input and output sides of an electrical circuit by a light transmission that is modulated by input current. Conventional optocouplers are configured to transfer useful input signals on an emitter side, transmit the signal across a dielectric insulation and detect the signal on an output side.
Typically, optocouplers are coupled to printed circuit boards. When the optocoupler is coupled to the printed circuit board, the shortest path between two conductive parts of the optocoupler, measured along the surface of the insulation, is known as the “creepage” path. Industry standards for printed circuit boards can stipulate minimum distances for creepage paths for safety reasons. Designs for printed circuit boards, however, can be driven to reduce size and increase component density on circuit boards to facilitate miniaturization and reduced costs which can lead to decreased creepage distances. Some printed circuit boards may include slots disposed between the input and output sides of the optocoupler to facilitate increasing the creepage distance. Conventional slots, however, can weaken the printed circuit board leading to flexing and/or cracking of the printed circuit board. Moreover, weakened printed circuit boards can further compromise solder joints of electrical components which can lead to increased body stress for the electrical components.